eIF5A is activated by virus infection or dsRNA and facilitates virus replication through modulation of interferon production

USP1 inhibits influenza A and B virus replication in MDCK cells by mediating RIG-I deubiquitination

The post-translational modification and stability regulation of RIG-I play critical roles in promoting IFN-I production and maintaining immune homeostasis. In this study, we found that ubiquitin-specific peptidase 1 (USP1) promotes RIG-I protein stability through deubiquitination, which in turn enhances antiviral immunity through the production of inflammatory cytokines, and inhibits the replication of influenza virus in MDCK cells. In contrast, USP1 knockdown inhibited the deubiquitination of RIG-I, decreased the RIG-I protein level, and significantly increased the influenza virus titer. Meanwhile, inhibition of USP1 expression did not have a significant effect on the proliferation of MDCK cells, suggesting that USP1 could be used as a target gene to establish a vaccine-producing MDCK cell line. The above results provide a more comprehensive understanding of the function of USP1 and the antiviral response mechanism, and provide a theoretical and methodological basis for the screening of target genes for the artificial establishment of high-yield MDCK cell lines for vaccine production.

A novel role of ETV6 as a pro-viral factor in host response by inhibiting TBK1 phosphorylation

E26-transforming specific (ETS) variant 6 (ETV6) is a transcription factor regulating the expression of interferon stimulating genes (ISGs) and involved in the embryonic development and hematopoietic regulation, but the role of ETV6 in host response to virus infection is not clear. In this study, we show that ETV6 was upregulated in DF-1 cells with poly(I:C) stimulation or IBDV, AIV and ARV infection via engagement of dsRNA by MDA5. Overexpression of ETV6 in DF-1 cells markedly inhibited IBDV-induced type I interferon (IFN-I) and ISGs expressions. In contrast, knockdown, or knockout of ETV6 remarkably inhibited IBDV replication via promoting IFN-I response. Furthermore, our data show that ETV6 negatively regulated host antiviral response to IBDV infection by interaction with TANK binding kinase 1 (TBK1) and subsequently inhibited its phosphorylation. These results uncovered a novel role of ETV6 as a pro-viral factor in host response by inhibiting TBK1 phosphorylation, furthering our understandings of RNA virus immunosuppression and providing a valuable clue to the development of antiviral reagents for the control of avian RNA virus infection.

Dengue fever in hyperglycemic patients: an emerging public health concern demanding eyes on the effective management strategies

Background and aims

Hyperglycemia, also known as diabetes, is a metabolic disorder characterized by elevated levels of glucose in the bloodstream. It can lead to the prolonged dysfunction, injury, and deterioration of several organs. In addition, dengue is a viral illness transmitted by mosquitoes that has reached epidemic proportions worldwide. In this article, we focused on the severity of comorbidities, difficulties in managing them, and preventive measures meant to lessen the risks associated with comorbidities in diabetic patients with dengue infection.

Methods

We explored a number of databases, including PubMed, Scopus, Embase, Web of Science, Google Scholar, and the Cochrane Library, for this review article using various related keywords.

Results

The findings of this review article indicate that elderly dengue patients with diabetes should be admitted to the hospital for close observation and early management using fluid therapy. An observed association exists between dengue hemorrhagic fever (DHF) and diabetes, indicating a possible consequence in this specific group. Additionally, patients with diabetes who contract dengue show elevated levels of inflammatory markers. Diabetes mellitus deteriorates the immune system, which exacerbates the progression of dengue fever. Cutting-edge technology and scientific research may assist in addressing the challenges that diabetes and dengue viruses pose in low- and middle-income countries. Implementing innovative diabetic care management is essential to ensuring consistency of care, improving a healthy lifestyle, and lowering patient risk factors and comorbidities.

Conclusion

Dengue fever has spread to epidemic levels throughout the world. Inflammatory markers increase and the prevalence of DHF is greater in diabetes individuals with dengue infection. Given the continued growth of dengue in Asian nations, it is imperative that we concentrate our efforts and resources on providing more precise and effective treatment for this emerging issue.

Hepatitis C Virus Dysregulates Polyamine and Proline Metabolism and Perturbs the Urea Cycle

Hepatitis C virus (HCV) is an oncogenic virus that causes chronic liver disease in more than 80% of patients. During the last decade, efficient direct-acting antivirals were introduced into clinical practice. However, clearance of the virus does not reduce the risk of end-stage liver diseases to the level observed in patients who have never been infected. So, investigation of HCV pathogenesis is still warranted. Virus-induced changes in cell metabolism contribute to the development of HCV-associated liver pathologies. Here, we studied the impact of the virus on the metabolism of polyamines and proline as well as on the urea cycle, which plays a crucial role in liver function. It was found that HCV strongly suppresses the expression of arginase, a key enzyme of the urea cycle, leading to the accumulation of arginine, and up-regulates proline oxidase with a concomitant decrease in proline concentrations. The addition of exogenous proline moderately suppressed viral replication. HCV up-regulated transcription but suppressed protein levels of polyamine-metabolizing enzymes. This resulted in a decrease in polyamine content in infected cells. Finally, compounds targeting polyamine metabolism demonstrated pronounced antiviral activity, pointing to spermine and spermidine as compounds affecting HCV replication. These data expand our understanding of HCV's imprint on cell metabolism.

Construction of a nomogram for predicting HNSCC distant metastasis and identification of EIF5A as a hub gene

Patients with distant metastasis of head and neck squamous cell carcinoma (HNSCC) often have a poor prognosis. However, early diagnosis of distant metastasis is challenging in clinical practice, and distant metastasis is often only detected in the late stages of tumor metastasis through imaging techniques. In this study, we utilized data from HNSCC patients collected from the TCGA database. Patients were divided into distant metastasis and nonmetastasis groups based on the tumor-node-metastasis (TNM) stage. We analyzed the differentially expressed genes between the two groups (DM/non-M DEGs) and their associated lncRNAs and generated a predictive model based on 23 lncRNAs that were significantly associated with the occurrence of distant metastasis in HNSCC patients. On this basis, we built a nomogram to predict the distant metastasis of HNSCC patients. Moreover, through WGCNA and Cytoscape software analysis of DM/non-M DEGs, we identified the gene most closely related to HNSCC distant metastasis: EIF5A. Our findings were validated using GEO data; EIF5A expression was significantly increased in the tumor tissues of HNSCC patients with distant metastasis. We then predicted miRNAs that can directly bind to EIF5A via the TargetScan and miRWalk websites, intersected them with differentially expressed miRNAs in the two groups from the TCGA cohort, and identified the only overlapping miRNA, miR-424; we predicted the direct binding site of EIF5A and miR-424 via the miRWalk website. Immunohistochemistry further revealed high expression of EIF5A in the primary tumor tissue of HNSCC patients with distant metastasis. These results provide a new perspective for the early diagnosis of distant metastasis in HNSCC patients and the study of the mechanisms underlying HNSCC distant metastasis.

Viral infection and host immune response in diabetes

Diabetes, a chronic metabolic disorder disrupting blood sugar regulation, has emerged as a prominent silent pandemic. Uncontrolled diabetes predisposes an individual to develop fatal complications like cardiovascular disorders, kidney damage, and neuropathies and aggravates the severity of treatable infections. Escalating cases of Type 1 and Type 2 diabetes correlate with a global upswing in diabetes-linked mortality. As a growing global concern with limited preventive interventions, diabetes necessitates extensive research to mitigate its healthcare burden and assist ailing patients. An altered immune system exacerbated by chronic hyperinflammation heightens the susceptibility of diabetic individuals to microbial infections, including notable viruses like SARS-CoV-2, dengue, and influenza. Given such a scenario, we scrutinized the literature and compiled molecular pathways and signaling cascades related to immune compartments in diabetics that escalate the severity associated with the above-mentioned viral infections in them as compared to healthy individuals. The pathogenesis of these viral infections that trigger diabetes compromises both innate and adaptive immune functions and pre-existing diabetes also leads to heightened disease severity. Lastly, this review succinctly outlines available treatments for diabetics, which may hold promise as preventive or supportive measures to effectively combat these viral infections in the former.

Comparative RNA-seq analysis of resistant and susceptible banana genotypes reveals molecular mechanisms in response to banana bunchy top virus (BBTV) infection

Bananas hold significant economic importance as an agricultural commodity, serving as a primary livelihood source, a favorite fruit, and a staple crop in various regions across the world. However, Banana bunchy top disease (BBTD), which is caused by banana bunchy top virus (BBTV), poses a considerable threat to banana cultivation. To understand the resistance mechanism and the interplay of host suitability factors in the presence of BBTV, we conducted RNA-seq-based comparative transcriptomics analysis on mock-inoculated and BBTV-inoculated samples from resistant (wild Musa balbisiana) and susceptible (Musa acuminata 'Lakatan') genotypes. We observed common patterns of expression for 62 differentially expressed genes (DEGs) in both genotypes, which represent the typical defense response of bananas to BBTV. Furthermore, we identified 99 DEGs exclusive to the 'Lakatan' banana cultivar, offering insights into the host factors and susceptibility mechanisms that facilitate successful BBTV infection. In parallel, we identified 151 DEGs unique to the wild M. balbisiana, shedding light on the multifaceted mechanisms of BBTV resistance, involving processes such as secondary metabolite biosynthesis, cell wall modification, and pathogen perception. Notably, our validation efforts via RT-qPCR confirmed the up-regulation of the glucuronoxylan 4-O-methyltransferase gene (14.28 fold-change increase), implicated in xylan modification and degradation. Furthermore, our experiments highlighted the potential recruitment of host's substrate adaptor ADO (30.31 fold-change increase) by BBTV, which may play a role in enhancing banana susceptibility to the viral pathogen. The DEGs identified in this work can be used as basis in designing associated gene markers for the precise integration of resistance genes in marker-assisted breeding programs. Furthermore, the findings can be applied to develop genome-edited banana cultivars targeting the resistance and susceptibility genes, thus developing novel cultivars that are resilient to important diseases.